import React from 'react'
class B extends React.Component{
    constructor(){
        super()
        console.log('B1,初始化')
    }
    render(){
        console.log('解析jsx')
        return <div>B</div>
    }
    componentDidMount(){
        console.log('B2,挂载成功')
    }
    componentDidUpdate(){
        console.log('B3,组件完成更新')
    }
    componentWillUnmount(){
        console.log('B4,准备卸载')
    }
}
export default B